Radio frequency (RF) weapons, also known as directed-energy weapons, use electromagnetic energy on specific frequencies to disable electronic systems. High-power microwave (HPM) weapons are a particularly fearsome type of RF weapon. RF, especially HPM, weaponry can generate destructive electromagnetic waves of such voltage and intensity to disrupt various electronic systems, including systems such as those used to control aircraft and other vehicles, communications systems, and other vital systems.
Most approaches to detection of RF weapons are directed to detection of their emissions. RF weapons are designed to produce the maximum amount of power possible, and to concentrate the power into the shortest possible pulse. In the absence of information of when a pulse will occur or what the frequency it will be, detection is difficult. Thus, an effective detector must respond to short pulses individually. Although the pulse width is likely to be short, the time between pulses can be expected to be long. Furthermore, one pulse may differ significantly from the next pulse.
U.S. Pat. No. 5,856,803, entitled “Method and Apparatus for Detecting Radio-Frequency Weapon Use”, to A. E. Pevler, describes technology for detecting RF weapons across a broad spectrum from a single emitted pulse. Received signals are analyzed to discriminate between RF weapon emissions and false-alarm rejection of other electromagnetic signals in the environment. When an intercepted signal meets criteria indicative of an RF weapon, an alarm signal is generated as the system's output.